.game{
    width: 800px;
    height: 600px;
    border: 2px solid #000;
    margin: 100px auto;
    position: relative;
    overflow: hidden;
}
.game .sky{
    background-image: url(./img/tiankong.png);
    height: 100%;
    width: 200%;
    position: absolute;
    top: 0;
    left: 0;
}
.game .land{
    background-image: url(./img/dadi.png);
    height: 112px;
    width: 200%;
    position: absolute;
    left: 0;
    bottom: 0;
}
.game .bird{
    background-image: url(./img/鸟.png);
    position: absolute;
    width: 33px;
    height: 26px;
    left: 150px;
    top: 150px;
}
.game .bird.swing1{
    background-position: -8px -10px;
}
.game .bird.swing2 {
    background-position: -60px -10px;
}
.game .bird.swing3 {
    background-position: -113px -10px;
}
.pipe{
    position:absolute;
    height: 100px;
    width: 52px;
    left: 500px;
}
.pipe.up{
    background-image: url(./img/shangshuiguan.png);
    top: 0;
    background-position: bottom;
}
.pipe.down{
    background-image: url(./img/xiashuiguan.png);
    bottom: 112px;
}
.info {
    text-align: center;
}
.score{
    position: absolute;
    z-index: 1000;
    top: 5px;
    left: 10px;
    font-size: 25px;
    font-weight: bold;
    color: #fff;
}